S-nitroso-glutathione

Giustarini D, Milzani A, Aldini G, Carini M, Rossi R, Dalle-Donne I. 2005. S-nitrosation versus S-glutathionylation of protein sulfhydryl groups by S-nitroso-glutathione. Antioxid Redox Signal 7 930-939. 

Tsikas, D., J. Sandmann, D. Holzberg et al. 1999. Determination of S-nitroso-glutathione in human and rat plasma by high-performance liquid chromatography with fluorescence and ultraviolet absorbance detection after pre-column derivatiza-tion with o-phthalaldehyde. Anal. Biochem. 273 32-40. 

This S-nitroso group is in equilibrium with other S-nitroso compounds formed by reaction of NO with small-molecule thiols such as free cysteine or glutathione (an isoglutamylcysteinylglycine tripeptide) ... 

S-Nitroso derivatives of the biological thiols—glutathione, cysteine (115) and homocysteine—have been considered as bioactive intermediates in the metabolism of organic nitrates and the endothelium-derived relaxing factor with properties of nitric oxide. A simple, rapid and reproducible method for separating these thiols from their... 

In addition, S-nitroso thiols can act as NO+ donors in S-transnitrosation reactions, which are of great physiological significance, or they can release NO when reacting with thiols [49] [50]. A further mechanism exists for S-ni-trosoglutathione, which is a substrate of glutathione peroxidase. In this case, the enzyme catalyzes the release of NO or a reaction of transnitrosation [51]. 

Peroxynitrite (ONOO ) is a cytoxic species that is considered to form nitric oxide (NO) and superoxide (Oj ) in biological systems (Beckman et al. 1990). The toxicity of this compound is attributed to its ability to oxidize, nitrate, and hydroxylate biomolecules. Tyrosine is nitrated to form 3-nitrotyrosine (Ramazanian et al. 1996). Phenylalanine is hydroxylated to yield o-, m-, and p-tyrosines. Cysteine is oxidized to give cystine (Radi et al. 1991a). Glutathione is converted to S-nitro- or S-nitroso derivatives (Balazy et al. 1998). Catecholamines are oxidatively polymerized to melanin (Daveu et al. 1997). Lipids are also oxidized (Radi 1991b) and DNA can be scissored by peroxynitrite (Szabo and Ohshima 1997). 

Nitrosothiols such as cysteine-NO, glutathione-NO, and S-nitroso-N-acetylpenicillamine (SNAP) are often used a nitric oxide donors. The biological effects of these compounds suggest that they do, in fact, release significant amounts of nitric oxide, but the mechanism of release is not at... 

The second approach [52] is based on the ability of low-molecular S-nitroso-thiols, namely, S-nitrosoglutathione (GS-NO) and S-nitrosocysteine (Cys-NO), to form DNIC in a direct reaction between Fe " and thiols [53-55] and differs from the former by the ease of performance besides, it excludes purification of gaseous NO from NO2 and the use of buffer solutions. All that is needed for DNIC synthesis is glutathione (cysteine), a bivalent iron salt, sodium nitrite, and distilled water as a solvent... 

Increased oxidative stress in the RAW 264.7 macrophage cell line is partially mediated via the S-nitrosothiol-induced inhibition of glutathione reductase (EC 1.6.4.2) (Butzer et al. 1999). Fujii et al. (2000) isolated a cDNA for rat glutathione reductase and constructed a baculovirus system to produce recombinant glutathione reductase on a large scale. NO donors (S-nitrosoglutathione, SIN-1, and S-nitroso-N-acetyl-D,L-penicillamine) inhibited the enzymatic activities of purified glutathione reductase. 

Exogenous NO in the form of a nitric oxide donor (S-nitroso-L-glutathione or diethylamine NO) significantly reduced lL-8 mRNA in cytokine-activated human endotheUal cell Une ECV304 (Fowler et al. 1999). 

Radomski, M.W., Rees, D.D., Dutra, A., Moncada, S., 1992. 5-nitroso-glutathione inhibits platelet activation in vitro and in vivo. British Journal of Pharmacology 107, 745-749. 

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